This invention relates to a container, and more particularly to a tray having adjustable stacking heights.
A common tray used in bakeries has two end walls for stacking and two shorter side walls for product visibility and to allow nesting. These trays typically nest by rotating alternate trays 90degrees. They are easy to blind stack (i.e. stack above your head where it is difficult to see any locating features). However, the requirement to nest the trays in a 90degree rotation makes the footprint of the nested trays larger than a single tray and results in a low nest ratio, which is limited by the height of the side walls.
In some of the known trays, one of the side walls is shorter than the other, so that it is low enough for removing product even when the trays are stacked. This is commonly called a dropside version. This lower sidewall may also be called a window. When the trays are stacked, it is advantageous for the dropsides to align on the same side of the stack, so that product can be accessed from any of the trays from the same side. However, the dropside is weaker and deflects considerably more than the opposite side.
Sometimes it is desirable for the trays to be stacked at a selected one of two selected heights, in order to minimize the stacking height to that required by the product in the trays at the time. This is usually accomplished by trays that stack at different heights when they are rotated 180 degrees relative to one another. However, this means that the dropsides cannot be on the same side of the stack when the trays are arranged in alternating 180 degree orientations in order to achieve one of the stack heights. Additionally, having two stack heights limits the ability to blind stack and the features to create this often cause the external dimensions of the tray to be larger. The larger tray size reduces the amount of full goods that can be shipped.